Question

A 72-year-old woman with small cell lung cancer presents with fatigue and confusion. Her serum sodium is 118 mmol/L, serum osmolality is low, and urine sodium is elevated with inappropriately concentrated urine. She is euvolaemic on examination and has had symptoms for more than a week. Which is the most appropriate initial management for her hyponatraemia?

Accepted Answer

Fluid restriction to 800-1000 mL/day

Answer

Normal saline 0.9% at 500 mL/hour

Answer

Rapid correction with 3% hypertonic saline to normalise sodium within 12 hours

Answer

Oral sodium chloride tablets alone

Answer

No treatment is required if she is asymptomatic

Practice question